Linux Iptables Open LDAP Server TCP Ports 389 and 636

The default Iptables configuration under CentOS / Red Hat / RHEL / Fedora Linux does not allow inbound access to LDAP service. How do I update iptables settings to allow access to the LDAP primary TCP #389 and encrypted-only TCP # 636 ports, while keeping all other ports on the server in their default protected state?

Under CentOS / RHEL you need to update /etc/sysconfig/iptables files. Usually you need to restrict access to an appropriate network block and network mask, representing the client machines on your LAN or WAN which will connect to your LDAP server hosted on RHEL.

Configure Iptables to Allow Access to the LDAP Server

Edit /etc/sysconfig/iptables using the text editor:# vi /etc/sysconfig/iptables Add the following lines, before the final LOG and DROP lines to give access only from 192.168.1.0/24 network:

Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.

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8 comment

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I have an LDAP server running on RHEL 6. When I do an LDAP search within that server, it works. But, when I perform the same search from outside, I get “Can’t connect to LDAP Server”. I have disabled the Firewall. Both ips are on the same subnet. But the same set up works from SLES 11(LDAP Server). What is different on RHEL 6. Any ideas? Thanks.

Hi sir I heard that linux server is good for proxy, I also read linux study guide but I don’t know how to config it. let me know squid 2.4 configuration step by step use in soho squid server . Pls mail me help me .

Hello everyone, i’m using PHP to edit iptables rules on centOs. In fact, i’ve configured the sudoers file do grant priviliges to my xampp user (nobody). But what make me loose my cool is that, whenever i try to edit iptables in php script, nothing happens. What else do I really need to do in order to make it go? I really need your help.